Sean Fitzpatrick left a lengthy suicide note at his home before Monday's shooting, Bragdon said.

"There is no doubt in my mind that the young man intended to commit suicide by having us do it," the chief said.

Bragdon declined to reveal the contents of the note other than to say the youth was explicit about his emotional pain and depression. Bragdon could not say why the student chose the school for his showdown with police.

The student was shot three times by officers who fired almost simultaneously when the student raised the handgun pointed toward them. Fitzpatrick was shot in the jaw, stomach and arm and remains in critical condition in a local hospital. Each officer apparently fired once, Bragdon said.

All of the approximately 2,000 other students, plus faculty and staff, were evacuated and no one else was injured.

Crisis counselors were on hand Tuesday morning as students returned to classes at the school, which is in the shadow of Interstate 90 in downtown Spokane. Principal John Swett and four student leaders posted a joint statement on the school Web site Tuesday morning.

"Yesterday, September 22nd, was a sad and difficult day for the community of Lewis and Clark High School," the statement said. "One of our own, a young man in the junior class, brought a handgun to school."

A classmate was puzzled by the incident.

"He was a real quiet guy, keeping to himself," student Sean Burke, who was in a class with Fitzpatrick as a freshman, told The Associated Press. "I really didn't think he would do something like that."

Fitzpatrick "didn't draw attention to himself. It must have been something pretty big that would have pushed him," Burke said.

SWAT team members who fired their weapons were placed on paid leave, a standard procedure in shootings by law enforcement officers, Bragdon said.

Bragdon said the student entered the classroom with a 9mm semiautomatic handgun shortly after 11 a.m. Monday, ordered a student teacher and several students to leave and fired once into a wall. He took no hostages.

The boy also sprayed the room with retardant from fire extinguishers, which made it hard to see, the chief said.

The first officers on the scene had the shooter contained inside the classroom by 11:24, 14 minutes after the first call, Bragdon said.

Marjan Khoee, 35, an Iranian exchange student at Whitworth College, told The Spokesman-Review the episode began as she was eating lunch with three high school students in Room 307.

"He just walked in, stuck the gun in my face and told me to get out the room," Khoee said. "I asked him, 'Is everything OK?'" He just calmly told me to get out of the classroom."

She said the boy looked familiar, but she didn't recall him from any of her classes.

After the other students followed her out of the classroom, Khoee said, she heard at least one shot being fired.

Shortly afterward, not knowing what was happening, senior Lee Pearson, 17, opened the door to the chemistry and physics lab and found a metal bookcase blocking the entrance.

"I was going to move it to get in there. As I looked up, standing five feet in front of me was the kid," Pearson told The Spokesman-Review. "He had a black pistol in his hand. He waved it as a signal to get me out of the room. I was kind of dumbstruck."

School officials triggered a fire alarm to evacuate the school. The nearby freeway was closed for nearly two hours in both directions.

Negotiators talked with the boy for more than an hour, and SWAT officers surrounded the classroom, Bragdon said.

"He was angry at everything. He was making threats about everything" but did not appear to be angry at any particular individual, Bragdon said.

When a negotiator told him his father had arrived, "he told us to send his dad away," the police source told the newspaper. "He said, 'I don't want him to see this.'"

Moments later, about 12:45 p.m., the boy abruptly stopped talking, put on his jacket, climbed onto the file cabinet and raised a handgun at officers, leaving SWAT officers no choice but to shoot, the chief said.

Preliminary information indicated the gun came from the boy's home, Bragdon said.

Evacuated students were bused to the nearby Spokane Arena, where their parents picked them up.

The city's schools do not have metal detectors, so any concealed weapon would not be detected, Superintendent Brian Benzel said. There are no plans to change that policy, he added.

The incident ended so quickly because the first officers to arrive immediately entered the school and went to the area where the student was holed up, Bragdon said.

The massacre at Columbine High School in Colorado, where law enforcement officers waited outside to assess the situation, has prompted police to make aggressive entries in such situations, he said.

Benzel said the school district and police had practiced for such an event, and police already had maps of school layouts.